Variable load brake



Nov. 28, 1944. c. c. FARMER VARIABLE LOAD BRAKEY ow kt H M 1 E m 9 U h TA N .5 NF R & E O t vC w ME ,A w 0 VI 5 L Q MMR wk mw m K Ni 71 Q wk m 9 0 \w a i: w R N R v d R m an m Mir No'v.v28 1944. c. c. FARMER 2,363,580

VARIABLE LOAD BRAKE Filed July so, 1942 5 Sheets-Sheet 2 INVENTOR J? CLYDE C4 FARME BY M w ATTO R N EY Patented Nov.28,1 944 i a n a a 2,3 80

viutmemi LOADAFRAKE U i :Qlyde C. Farmer littsburghi Westinghouse Air ,Brake., C

i rg, a corporation ofiienhsvlvania, e J I Application July 30, 1 942,S erial Nnfiiifiz ssfia H i, i 25 cl ms. ((21. 188 195) This 1 inventionkrelates to varia le load' br-ake apparatus *for railway vehicles and i more pare ticulariy to that type 'of apparatus in which the lever-age thereof may 1 be automatically varied in accordance nth-variations in the weight of the load bnihe vehic1 to correspondingly vary the f orce-with' vvlfiich the fbrake adapted to be iii pliedff f object ';of the invention is; to provide an i npreved -variabi ad brake apparatus of the tes 91 pi ie s h r l j h cylinder ston over that; required ;for

tive means employed for positively locking the apparatus in anyof its conditioned positions diiiereni, locking mechanism which may: be substituter i tor the locking mechanism :shown in f i Fig; 9 is a horizontal sectional view of the locking mechanism shown in' Fig. 8, Q i Fig; i0 is a fragmentary sectional view t Fig. 11 is a diagrarnmatic view partlyin sectionof a variabl-e load brake apparatusembodyc d-jpg iivfsaispredeter i ed limit. Aflfur ther feature resides, in the automatically opera- Farmer No; 2,031,213, issued February 18, 1936,

l shown in Figll 'o ithe-accompanying drawings, the variableyload iiuid -pressure gbrake apparatus' may eomprise a brake-pipe l, asbrake controlling valve: device '2, acoinbined "cutout cock and centrifugal dirt co11ectorr3, an aux iliary-reservoir 4, an emergency reservoiri, a change-over control-"valve device- 6, a pilot valve device "'1', "fb W0- =W 1g inggnfrechanismst, one of Whichfis idi-sposedatfleaeh 0f the vehicle, an adjusting mechamsm-e, a; *l0cking mechanism l0, alfbrakeoylindeif I and a -pair of cjrlinder'levers 1 device 2 shown a The 9 r ke controlling valve is of the AB but may be chany other desired typef mechanism may he of substaritia'l'ly the same construction-5 and have *the same operating characteristics-ja the fAIB valve device} tuily 'described in the] patent to Clyde-(L "and view of this it is deemed-unnecessary againsta cidQI taI movement therefrom and for 'auton atica11vun1ockingthe apparatus to permit its inten Other objects and advantages will appeani n th fo llowing' detailed description of the inven- "In the accompanying drawings 85 "onal operation from one ofits conditioned positions to another.

to show" and describe the device in detail. "It

wil'l ef course be understood that this eeha m in operates'upenaservice-reductionin brake pip pressure to supply* fluid [under pressure to eff' al service application of the" brakes, upon emergency redi ction inbrake cpipe pressure Fig; lis a diagrammatic view, partly in section, ofa variable load brake apparatus con- 1 stifucted iniaccprdance with the invention.

fFig. 2,is a fragmentary sectional view taken shown inEig. "1, v it as JIPig. 3 is a cross-sectional vie'w taken on I the *Fig." 4 is an enlarged sectional view of the change ove'r control valve device shown in outline in Fi .1,

; Fig. 5 is an nlarged sectional viewof .the pilot valveiievice shown in outl ineim Fig. 1,

Rig. 6 is afragn entary sectional View taken on--the1ine"6+5 of Fig. 5, i 1 pFig. 71s a fragmentary sectional view taken on the line 'I -,-"'I of the adjusting mechanism showninfiliig. 1,3 ,r Fig'xaf is a fragmentary sectional view of a te supplyjfluid underipressure toefiect an emerencyapplic tier-i ef the {brake-s, and upon an lease gist-lie brakes ana me charging of "the brake equipment. -i

The';combined I dirt coilector- 3- 30i {tho-usual well known cone struction -and for this, reason it is deemed jun-- necessary tofshow and deScribe the device in detail.

N dbetweenthe casinfg of the. brake controllingwalvedevice 2 and, the; combined cut out cookcentrifrigahdirt collector device 3 is a filler piece 15 which, at one, end registers with the out-let passage"ofthej devicej3 and, lat the 0th :end withgthe brakegpipfpassage of the b ake qritrp i 'Y v c' iz, whic brake p j i iip fi a uisqwellfiknown is; in constant} p Piston chem-v open communication with the hers. (not,v hown), of the servi portions ofthe"device 2.

mm ses alien The inlet passage of the device 3is connected by a branch pipe 5 to the brake pipe which passage i normally open to the outlet passage, but which is adapted to, be closed through the medium of the usual rotatable cut-out plug valve, not shown.

The change-over control valve device 6 may comprise a casing in which there is slidably mounted a piston l8. At one side .of this piston there is a chamber |9 which is constantly connected through a passage with the atmos phere. At the opposite side of the piston there is a valve chamber 2| which is' constantly connected through a passage and pipe 22 to the side outlet of the filler piece l5.

Containedin valve chamber 2| is a slide valve 24 which is adapted to be operated by a piston 53 having slidably mounted therein a spring seat 4 54. Interposed between and operatively engaging the spring seat 54 and the closedend of the bore is a spring 55. The spririgsea't 54 is provided with a stem 56 which extends to the exterior of the bore 53 and is connected at its outer end in any suitable manner to the operating member 39.

stem 23 carried by the piston l8. Contained in chamber l9 and acting on thepiston is a spring 25 which, at all times, is, arranged to urge the piston, piston, stem and slide valve toward the position in which they are shown in Fig. 4 of the drawings. e

The pilot valve device 1, comprises a casing having a chamber ,26 which isopen at one end, by wayof a passage21, to a pipe 28 leading to the seat for the slide valve 24 in the change-over control Valve device 6, and which is open at the oppositeend, byway of a passage 29, to a chamber 30. communication with a volume reservoir 3| by way of a pipe 32. p

Contained in chamber 26 is a pair of valves 33, 34. The valve 33 is adaptedto seat on an annular seatrib 35, surrounding the passage 21, to ut off communicationlbetween said passage and the chamber. The valve34 is adapted to seat on an annular seat rib 36, surrounding the passage 29, to cut ofi communication between chambers 26 and 30. Also contained in chamber 25 "and interposed between and operatively engaging the valves 33and 34 is a spring 31.

The valve 3415 provided with a stem 3a which extends through the'passage 29 into the chamber and at its outer end engages an operating member 39 which is hingeel te the casing by means of a pm 391), as best shown in Fig, 6 of the drawings.

I'Ih'e casingoi the pilot valve device 1 is also provided with a chamber 40 which is connected to the locking mechanism |0 by way of a pipe 4|. J'I'he chamber 40 is connected at one end to a passage 42 which is connected to the passage 21. The chamber is connected at the opposite end to a passage. 43 leading to the chamber 30.

Contained in chamber 40 is a valve piston 44 which at one end is adapted to seat on an annular seatrib 45, surrounding the passage 42, to out on communication between chamber 40 and passage 42. At the opposite end, this valve piston is adapted to engage a sealing gasket 46, surrounding the passage 43 and carried by the casing,.to cut off communication between chambers 40 and 39. This valve piston is provided with a bore 41 containing a spring seat 48. Interposed between and operatively engaging said spring seat. and the closed end of the bore is a spring 49.

The spring seat 48 is provided with a stem 50 which extends through the passage 43 into .the chamber 30, which stem is rigidly connected to a valve piston 5| constructed and arranged to engage a seat. rib 52 surrounding the passage 43 within chamber. 4|].

The valve piston 5| is'providedwith a bore The chamber 3|] is in constant open For the purpose of controlling the operation of the operating member 39, a rotatable cam 51 is provided having aperipheral cam face 58 adapt ed to operatively engage the lower surface of the member. 5

The cam 51 is secured to an operating shaft 59 which is rotatably mounted in the casing and secured to the outer end of this shaft exteriorly ofthe casingis an operating lever 60. v, V It will here be noted that a spring 39a is interposed between the upper surface of the operating member 39 and the upper wall of the chamber 30 and is operative, at all times, to urge the member into engagement with the cam face 58.

The weighing mechanism may comprise at each end of the vehicle an actuating device 6| which is rigidly secured in any suitable manner to a spring supported partsuchfor instance'as the body bolster or any other suitable part of the vehicle body. The device comprises a twopiece casing having clamped therebetween a diaphragm 62. At one side of the, diaphragm is a chamber .63 which is in constant open communication with a pipe 64 extending from the device at one end of the vehicle to the. device at .the opposite end of the vehicle, which p'ipe in turn is connected to the locking mechanism II] by means of'a pipe 65. At the opposite side of the diaphragm 62 in 'each device there is a chamber 66 which is in constant open communication with the atmosphere by way of a passage61.

Contained'in each chamber 66 there is a diaphragm follower 68 having a stem 69 which extends to the exteriorof .the casing and which, at its outer .end,.is connected to a'le'ver 10 by means of a pin 1!. Alsocontained' in'each chamber '66 and interposed between and operatively engagingthe diaphragm follower 68- and the .inn'er'wall of the chamber is a spring 12.

The lever 15 at each end of the vehicleis rock ably mounted intermediate its. ends on a pin mounted'in 'a bracket 13 carried by the casing. One end of the lever 10 is connected to a rod 14 which is provided with a foot portion 15 which portion is adapted to be moved into engagement with a stop member 16 carried. by a fixed or unsprung part of the vehicle such for instance-as the truck frame. The foot portion 15 and stop member 16 are so arranged that whenthe vehicle is empty there will be a clearance space between them which will be suflicient topermit the usual vertical, vibrations of the body relative ,to th'e truck frame and vehicle wheelswithout danger of their engagement with each other thuslrelieving the mechanism of damaging forces which might otherwise be transmitted theretol The oppositeend of the lever. 10 is connected to one end of a cable 11, which cable. passes-over a plu-.

rality of pulleys 18 mounted'on the-body of the vehicle. It .will be. .noted that since thefoot portion 1.5 is-supportedby a spring supported QiBBBiEBD and the maximum el'earance Zwith l the. *v'ehi'cle fully loaded. I I I 'I'he brake cylinder II is ofthe usual well known typehaving a cylinder fifl which is rigidly secnred to the-underside of the vehicle body and which contains the "usual piston (not shown') having a pnsh rod :81 which projectsbeyondone. endiofithe cylinder. The outer end' 'oflthezpush rod. a1 is operatively'oonhe'cted to "the one end of ethe' horizontally disposed. live. or floating brakexcylinder'lever 12 the other end of the lever being operatively connected with atpull rod: 83 leading tootherbrake rigging "elements; not shown. I (Formed .on the cylinder 1810* is a lug 85, whichcarries a :pin 86 upon whieh one endof the dead brake cylinder lever II3 is pivotally I mounted. The other end of the lever I 3 is connected we pull rod 88, which may be connected in the usual manner to other members of the brakerigging. II I I I The levers I2 and I' 3 are-I'operatively connected togetherintermediate theiriends by a rod F90;

The rod 90 is operatively'connected to the live cylinderlever by. means of awfulcrum pin SI which is arrangedto slide 'withina longitudinal slot :9-2 formed in the u'leverl'2. 'Iheop- ,d-inalslot 94iiormedlin the 'lever* I3.

:It is obvious thatany variation in the position ofthepins 9| and-93 withrelation to the levers serving toisupportf the r rod: in: its horizontalposition. 1. The member i9I5is also provided withia.

base: portion IIIlI'I .to which the inner end of tied 9-9 is rigidly :se'eured, which base-portion IOU-is provided "with a 'springseat =I70I and is slidabl'v guided horizontally -by spaced lugs #93! carried by zand 'extending outwardly: from ea brake cyline I dervsupporting: member *9! rigidly carried by the vehicle body. '-Interpose'd between and operatively engaging the 'spririg-seataml and a-bracket:.IIl2 nigidiywo'arried by the vehicle body is a spring I503, which is I 1 held in place by I a horizontally disposedrrod -wl-1ich1rod, at its inner end,-"is:sup-

ported b :andisecure'd'tothe spring seat I-IIHand Whieh at -itsouter end isslida-bIyi guided the 1 bracket .I-TBZ. I Suitably. journaled on a pin lcarried bvthehorizontally extendingrod 99 is a. pulley I104 under wh'ich p'asses the cable '11 which as hereinbefiore mentioned is connected at each end of= the I vehicle atone end of the=lever-7I'01 iconstituting ra part oftheweighing mechanism ll'."

' in "any suitable' mannergiand slidaibly mounted in IZ -an-dI 3respectively, willresult in a variation I in the leverage of the apparatusand"thereby-a variation in the braking sp'ovver of the brake rigging. 5 l 11 I If the pin 9I is moved longitudinally in a 8I thearm of the lever I2 to which thepizsh rod is connected, will be correspondingly lengthened,

direction away .fromthe brake cylinder push rod 1 l so' that when the brake cylinder device is operated the power transmitted by the opposite or outer endfof the lever to the pull rod :8'3,will becorrespondingly increased. If the II pin is moved from the outer end of the slot in a direction toward the push rod III .the power transmitted to thepull rod will be decreased.

' It-is-also obvious that ifthe pin 93 at the 0p 1 i *The r'od' @99 has screw threaded connection :at

its outer-end with a tubular memberxlflswhaving teeth" which are a'da-pted to be engaged by; 100k- I ing'iplates or pawls 'liflfi comprising a part of the-locking mechanism I0. I

I The locking mechanism JI 0 comprises a casing I I0 which is rigidly secure'd to the "vehicler:-body said' casing are tour of thelocking plates torupawls l llfi 'iiust referred to. "Each plateor pawl: IOBAis provided with an"op e'ningnl I I,1 as ibestishown in I Eigbzfthrongh whioh the tooth portiom of the tubular member I 05' connected "to thei-rod 99 ex-'- tends. "Two-of}.-the p1altesor pawls I OB areI pro-.- vided eat one endwith lugs I lluwhichare con nected to one end of :an actuating lever M13;

Thepthertwo platesor pawls lzllfi are provided at the same end with lugs I which :are: connected to the -opposite end of the actuating lower 3. The plates I06 at their 'oppositeend are arranged.

to be engaged ried -bya piston I16; I r I I The actuating lever I I3 tisiconnected intermediate itsen'dsto one end'of a' plunger: or push posite: end of the rod 90 is moved outwardly in.

a .direction away from the brake cylinder .I I the power transmitted by the outer end of the cylinder lever I3 to the pull rod -88 will be correspondingly I increased. Ii the pin is moved inwardly from its outer positionthe' power transmitted to the pull rod'will' be decreased.

It will be understood that the braking .force may be varied by shifting the rod 90 and pins 91 and I93 relative-tothe levers I 2 and 13 without increasing brake cylinder piston travel. The slots 92 and 94 are'so arranged thatthe travel of. the brakecylin'derpush rod-will be the same I regardless of the positions of theipins 91 I and 93 with relationto the-cylinder levers. :Thus, it

will be seen that thebraking force of the rigging maybe varied without necessarily varying the pressure of =fiuid in the. brake cylinder.

I t-Eor shiftingtherod SOreIative to the-brake I cylinderlevers I2 and I 3 so as to provide-a higher leverage ratio-for ailoaded car than for.

anempty car, the adjusting mechanism 9 is provided. y

."I'he adjusting mechanism S may comprise a horizontally movable member 95 having a tubu- L 13,; sleeve portion as which the rod su is slidably niountedand also having a-horiaontally exe red: I I9 havin'g a spring-seat or coll'ar I I1! which is slidably mounted in a cylinderbore I .I 8. in the casing; "Ihe opposite 'endlofthe plungerqiswslidably guided in a "bore I20 provided in a cover portion II 21I of the casing. :Surrounding the p'1unger and: interposed between and operativelyxaengaging the spring seat -I I1 andthe cover portion I 2 'I is a spring 122, which, as will hereina'fter appeawa'c'ts to move the plates or pawls I06 into locking engagement with the. toothed portion of the tubular member lflion the "rod 99.

Thenpiston' H 6 has at one I side thereofa cham- I ber I23 which is connected to ing to the pilot valve device I. The pipe leading from pipe 64 is connected to this chamber by Way of a passage I24 containing .a ball check; I valve I25 which prevents flowtof fluid from I chambers I23 to the pipe .65. Contained' in;

chamber I23-is a valve I26 having a stem I21.

The outer end of this valve stem is adapted to .be,

engaged by the outer face ofthe piston IIB, .jIn terposed between and operatively engaging .the

backlof the valve I26 and the inner wallof the chamber I23 is a springl I28 which, at all times, tends to move the'valve into engagement "With-Na va1veseat|29. I II -At' the opposite: side of. the. piston. 1H .6- :there is the jpipe l l fleada chamber I which is connected by way of a passage I3I, containing a ball check valve I32, to'the passage I24 at a point located intermediate the ball check valve I25 and the pipe 65.

In brake apparatus it is essential that sufficient clearance be provided between the friction braking surfaces of the brake elements as for instance between brake shoes and the treads of the vehicle wheels when the brakes are released to insure against any possibility of the elements engaging each other. It is desirable to take this clearance up quickly and without requiring an increase in brake cylinder piston travel when an application of the brakes. is initiated. With the brake cylinder lever arrangement shown in which th'e'leverage is varied according to the weight of the load carried by the vehicle by moving the pins 9| and 93 longitudinally of the levers the clearance between the braking elements must be greater than is provided with a brake in which the pins 9| and 93 are not adjustable. In order to provide the desired clearance and the rapid take-up of such clearance a toggle mechanism I is provided which may comprise a pair of levers I36 and I31, the adjacent ends of which are pivotally connected together by means of a pin I38. The opposite end of the lever I36 is pivotally connected to the base portion I00 of the member 95, while the opposite end of the lever I31 is pivotally connected to the sleeve portion 98 of the member 95.

The pin I38 in addition to connecting the adjacent ends of the levers I36 and I31 together also serves to connect these ends. of the levers to one end of an actuating rod I40. I40 at its opposite end is pivotally connected by means of a pin I4| to one end of a rod I42 and alsoto one end of a horizontally disposed lever I43. The rod I42 at its opposite end is connected by means of a pin I44 to the lever 60 which is secured to the operating shaft 59 of the pilot valve device I.

The lever I43 is connected by means of a pin I45 to the outer end of the push rod 8|, of the brake cylinder device and is provided with an arm I46 which is arranged to carry at its outer end a roller I41, which roller is adapted to travel in a tortuous path fixed by a guide slot I48 provided in a portion carried by the fixed. brake cylinder supporting member or bracket 91.

The pin I45 is supported by a pair of rollers I45a which are rotatably mounted on the pin and which are arranged one on each side of the connection between the levers I2 and I43 and push rod 8|, which rollers are, as shown in Fig. 1, guided by the-member 91 within a slot I45b one of the rollers being omitted in this figure in order to more clearly illustrate said connection. The guide slot I45b insures movement of the connection between the push rod BI and the levers I3 and I43 in a straight line.

Operation Assuming the vehicle, embodying the invention; to be empty and separated from a train, the

The rod cam surface 58 is out of engagement with the hinged member 39. With the cam 51, in this position the spring 39a acts to maintain the hinged member 39 tilted downwardly from the position in which it is shown, thus permitting the spring 31 to maintain the valve 34 in seating engagement with the seat rib 36, Furtherwith the member, 39 thus tilted the. spring seat 54 rests on a stop ring I50 carried by the valve piston 5|, the valve piston 5| being unseated and the associated spring seat 48 resting on a stop ring I' 5| carried by the valve piston 44. With the spring seat 48 engaging the stop ring |5| the valve piston 44 will be out of engagement with the seat rib 45 and in engagement with the sealing gasket 46.

Now, when the empty vehicle is placed in a train, the brake pipe I will of course be supplied with fluid under pressure, the brake pipe throughout the train being fully charged to the normal pressure carried before the train is put in motion. Fluid under pressure supplied to the brake pipe flows through the branch passage I6, the combined cut-out cock and centrifugal dirt collector 3 and filling piece I5 to the several chambers of the brake controlling valve device 2 which are to be charged and to the auxiliary and emergency reservoirs 4 and 5, respectively, in the usual manner.

Fluid under pressure flows from the side out let passage in the filling piece I5 to'slide valve chamber 2| inthe change-over control valve de-' vice 6 by way of pipe 22. With the change-over control valve slide valve 24 in its innermost position, as shown in Fig. 4 of the drawings, fluid under pressure flows from the valve chamber. 2| to pipe 28 from whence it flows to passages 21 and 42 in the pilot valve device 1. The changeover control piston and slide valve remain in this position until the pressure of fluid in valve chamber 2| has been increased sufficiently to cause the. piston and slide valve to move outwardly against the opposing pressure of the spring'25. As will hereinafter more fully appear, an increase in the pressure of fiuid in the valve chamber 2| to thirty pounds will cause the piston and slide valve to move as just described.

Fluid under pressure supplied to passage 42 flows past the unseated valve piston 44 to the chamber 40 from whence'it flows to chamber I23 in the locking mechanism I0 by way of pipe 4|. Fluid under pressure acting in chamber I23 causes the piston H6 and piston rod II5 thereof to move in a direction toward the left hand as viewed in ,Figs. 1 and 2 of the drawings. the outer end of the piston stem II5 engages thelocking plates I06 movement of said piston and stem in a direction toward the left hand causes the plates I06 to move in the same direction against theopposing pressure of the spring I22. The locking plates are thus moved out of engagement with the toothed portion of the tubular member I05 on the rod 99, thereby unlocking the adjusting mechanism 9.

The piston I|6 continues to move in this direction until brought to a stop by its engagement with a stop I55 carried by the casing. The piston when it is thus brought to a stop will have first covered the passage I3I cutting ofi the communication between the passage and chamber I30 and then uncovered the passage |3I thereby establishing a' communication between the passage and the chamber I23.'

Since the rod 90 in the same direction, which rod shifts the pins 9| and 93 "a short distance along the slots 92 and 94, respectively, in the levers I2 and I3. The slots 92 and 94 in the levers I2 and I3, respectively are so arranged that the pins, as they'are moved, tend to move the outer ends of the levers toward each other thereby actuating the pull rods 83 and 88 to actuate thebrake rigging (not shown) to bring the usual brake'shoes nearer the treads of the vehicle wheels.

"It will here be noted that the limited movement of the push rod 8| thus far described causes the levers I2 and I3 to operate to alsoactuate the pull rods 83 and 88, but the movement of the levers due to the movement of the pins 9| and 93 and to the movement of the levers about the pins is insuificient" to cause the brake shoes to engage the treads of the vehicle wheels, so that there will be no material braking forces acting to oppose the movement of the pins outwardly along the slots 92 and 94 respectively. As a consequence the mechanismwill be free of excessive stresses which may tend to damage the mechanism.

As the brake cylinder piston continues to move the'push rod 8| outwardly, i. e. toward the left hand, the roller I4! carried by the lever I43 enclearances between the associated parts are very close, cause the connected ends of the toggle links and the arm 88 ofthe pilot valve device I to move toward the right but such movement will be so slight that it will be negligible. From this it will be apparent that after the roller I4I enters'the left hand end of the slot I48 the lever I43 will in no way cause a material operation of the toggle links and arm 69 even though the piston travel may be excessive.

The push rod, as it continues to move forwardly as just described, actuates the lever- I2 and thereby the lever |3 in the usual manner to move the pull rods 83 and 88 to cause the brake shoes to frictionally' engage the treads of the vehicle wheels.

It will here be noted that the initial movement of the push rod 8| and connected lever I43 will effect movement of the rod I42 in a direction toward the left hand thereby rotating the lever 80 of the pilot valve device 'I in a clockwise direction. Rotation of the lever 89 in this direction rotates the shaft 59 and thereby the cam 51. As the cam 51 is thus rotated the surface '58 of the cam exerts an upward pressure on the member 39 against the opposing pressure of the spring 39a and causes the member to be moved into the position in which it'is shown in Figs. 5 and 6 of the drawings.

With the cam 51 thus positioned the valve 34, throughthe medium of the stem 38, is moved out of engagement with its seat rib 35. At the same time the spring seat 54 is moved, through the medium of stem 56, out of engagement with the ring stop I59 and through the medium of the spring 55 the spring seat first moves the valvepiston 5| into engagement with the seat rib 52 and then acts to compress the spring. I

The, valve piston 5| acting through the medium of the stem 59' moves the spring seat 48 Outer engagement with the ring stop I5I. Spring seat 48 acting through the medium of the spring 49 first causes the valve piston 44 to move into engagement with the seat rib 45 and then acts to compress the spring thereby positioning the various parts of the pilot valve device I in the position in which they are shown in Fig. 5 of the drawings. The spring 49 when'compressed as just described will be of such a value that it will prevent the unseating of the valve piston 44 by a pressure in passage 42 or less.

Release of the brakes with" the equipment coaditzoned for empty our operation When it is desired to effect the release of the brakes the brake pipe pressure is increased in the usual manner, causing the brake controlling valve device 2 to function to establish communication from the pipe I and consequently from the brake cylinder II to the atmosphere. The control valve device also functions to supply fluid under pressure from the brake pipe I to the auxiliary reservoir 4'. v

. When the fluid under pressure is vented from the brake cylinder II the push'rod 8| is moved into the cylinder in the usual manner thereby causing the brake cylinder levers I2 and I3 to effect a release of the brakes on the vehicle in the usual manner. When the push rod 8| has returned to the position in which the roller I41 is about to enter the right hand end of the slot I48 the levers I2 and I3 will have been moved a suificient distance to relieve the brake 'shoesof braking force. From this it will be-understood that the apparatus as a whole is now relieved of brakingstresses. It will be understood that up to this time the operation of the lever I43 has not imparted any material operation of the toggle links and arm 69.

Now as the roller I41 traverses the right end of the slot I48 a clockwise rocking movement about pin I45 is imparted to the lever I43, the outer end of the lever acting through the medium of the rods I49 and I42 to actuate the toggle links I36 and I 31 and'the arm 69 to their normal positions of rest as shown in Fig. 1. The toggle links as they are thus being moved to their normal position cause the member 95 and associated rod to be moved inwardly toward the brake cylinder, the rod in its movement shifting the pins 9| and 93 in the same direction along the slots 92 and 94, respectively, in the brake cylinder levers I2 and I3. The pins 9| and 93 as they are thus shifted permit the levers I2 and I3 to move so as to insure adequate clearance between the brake shoes and treads of the vehicle wheels. v The arm 68 as it is being moved actuates th several parts of the pilot valve device I tov their normal positions of rest as shown in Fig. 5.

Automatic change-over operation of the equip- I ment on a partially or fully loaded vehicle Assuming now that the brakes on the vehicle are released, the brake pipe deplete of fluid under pressure and the vehicle in the process of being loaded. Under the influence of the weight of the lading, the vehicle body will move downwardly relative to the vehicle truck, due to the compression of the usual body supporting springs by the increasing load. Since the weighing mechanism 8 is carried by the vehicle body, the

of thirty poundst of the venue;

foot; I 15: will I be; moved: downwardly;- relativeto therfixed-I ;stop-li carried by; the: vehicle truck, I so ithat as then load? on I the vehicle is increased I Iliidssfcorrespondingly I I increased; I

the-clearancebetween .theaShOe: 151i and {the :stop I fluid underI pressureI I- is supplied thereto the several. chambers of: thereco'ntrolling valve-:- device 2 andzgthe auxiliary and emergency "reservoir 4 andifi; respectively, wili be charged 3imthe--usual ticnwwith 'an-Iempty vehicle. At the same time, fluid-- under pressure flows fromn the filling: piece I5 through: the circuit hereinbeiore traced in connection with anempty vehicle to the chamber I23 I of the:;locking mech-anismv'lfl. The increase int: the-pressure Iotfluidin chamber- I 23 causes movement: of: the piston I I I B I ina 1 direction r'IItowands theiI ileitr:handzagainst. the: opposing "action at .therspringr l 2 2 toeffiect 'operationof '1 the look ing plates I06 to unlock the adjusting" mecha e nism 8 and at; :thes'ame time to establish com- I manner as-Iihereinbeiore' mentioned incomzec I therbrake shoes will, becgreaterI-rthamthatzapplied tor empty -brakingz; I

Release of ih6b7fke$ on a partially or ft ilPy' tbqded I When fluidunder pressure is released irom the brake cylinder II to Iefiect a release of the brakes in the usual manner andwhen the-push rod 8I I has returned to Withinapproximately three inches of: its full releaseI posit-ion the action of spring -I 03IIIwill cause the armsII I36 and I3I1-I pi the toggleimechanism I35: to Ibe 'positionedyas shown thus permitting therod 90 to drop; in the slots 92 and 94 I to f the adjusted position called for by the load on the vehicle soIas tmptovide adequate brake shoe clearance -y vhen e the I- 'hr akes a reereleasedt on the -.vel-1icle .aneapplied th partsof the; pilot: valve device I I As herein iore ImentionedRyhenI ItheIDrakes v rI ie p ra n w It m ihe I position in theyI arecshown;in EigI SL mnni'cation f through which I I fin-id" under pressure isrssupplied to :--tlIe* chambers* 63 'zof the weighing vazlvedevicesWI disposed. one at "each endruofzthe vehicle, 'in' r identically the same I manner" as al"I-' ready described in connection with I an-I empty vehiciei I It -Iwin be: understood fromI'the I-foregoing dcscription of the functioning of the equipment on an empty vehicle that fluid under pressure supplied to chamber63 of each weighing device FIfcauses the {levers-"1U of each device to rock about their'pivot'pins until the foot 15 attached tobne end therof engages the stop I6 at each SincethecIearan-ceortravel between the-foot! 5 and the-stop 16' is dependent upon th'e load carried by the vehicle, and since tiie cabie'n attached to theopposite end of the lever TU is passediinder'thebuiley I04, the pulley III 0d 99, member 95,toggle link I 36 and I31 a od "QU offthe"adjustingmechanism 9 will b'e move doutwai-dly against the opposing :action of the spring I 03 atdistan'ce called for by, the weight of the lading, the toggle links serving as the actuating medium between the rod lla and the member 951 fl he'rodflll as it is being moved outwai'dly'shiftsthe pins-9I and 93 111th? same di fejction along thesiots 92 and Min thezlevers Nowwiihen the pr ssure in thestapipe r gle I-nechanism I I35 operates to cause the mod 90 to move further: outwardlyin, therslotsaz and 94 I in the same manner as-hereinbefore described in connection with-I empty vehiclebraking I and I as before described continued movement oii;the push rod 81; eflectsI operaticnHofI-the brake cylindei" levers, t2 and I3-Ito cause the pull rods 83-and ,88 to apply I the usual I brake shoes against the vehicle Iwheels. SinceIIthepinstl and I 93Ihave been movedIoutwa-rdlyagreater distance than tori. empty braking the, braking power applied-I to I def e r mm bQi I eI iliw II gency reservoirs.tothehrakecylindenl I Application of the trans ction ca m-fi s cue-o t I in setting a at tutti. a' traii'Lt lie mtsestts plingsrareI IpaiztedI-which permits ltheI brakg'pip'e pressure to reduce; rapidly Ito Iatmosphefictprese sure which rapid reduction in Jbrake Lpipe pres sure causes the.I.brake controllingtfvalve deuiceqi;

and einezq I I "InIIefEecting sachets applicationlfgof the brakes the .IvariableI' load appatatusIwillII function in Isub stantiallyflthel IsamermannerI as it does I when effec'ting IaI service applicationIl otI the t b l'fikBS faith I exception that thelI change over control. valve device, 6 I operates, Ifwhen the brakes-pipeppes-,

i sure has.,beenreducedI.belowl thirty} pounds, to

; itlflowsto-[thebrake controlling;valvehdevicen2 I scription Ithe changeeover. control valve device 6 lowinggdescription;

connect t mes: chambenIQIZl, andI thereby; the pipe 28 to .thebi'ake pipei by way of t pipe I 22, I

I In releasing" the brakes following ,the I app ica; tion, the pilot valve device. 1 I functions difirentt; than when. releasing the bta kes. followingt a serviceI I.a.pplication} seentrom the Ito-ls When the car is again connected- II-in. I as train and it is desired, to efiect release: otItheI.b :akes following such an application of the Ibtakes .I fluid under pressures-is supplied I to the. brake pipeI-I I .II the" well I manner, I from. whence and the change-over control. valvedevice atin the manner heteinbefore described-in. connection with initialcliaicging;ofItheequipmenta As, w n he understood IIfrom theI foregoingdo and} the ,IpilotI I valve I devic 1 will, at; this time;

bothhbei positioned as illustrated in Figs. 4 I-andI 5 respectively, I thus I fluid I- undes-Ipixessure supplied to the:- changeI-over,; control valve; device It flows by way-of pipeI 28 to chamber I 215th the pilotyalve devices. L; Since; ashereinbeiore I mentioned, spring 49in thepilotvalve I maintains I-thevatve piston; 44 seated, against an opposi-ng.rpressure I oi approximately-I30pounds-thisvalvei-pistomwill remainvseated I with anrincrease inkpressurein chamber 21 and connected chamber 4-2. However, since the spring 31 I is-ofa lowvalue a slight incteaserin the pressure 'offiuid in chambeen will; cause the valve 33I tobe moved out of engagement with its seat 35. I I

IWith theIIvalve 35 thus unseated fluid under pressure supplied to chamber 21 flows past the unseated valve 35 ItoI chamberI zfi Ifrom Iwhence I phere by way of pipe 28, cavity I'I in slide valve 24 of the change-over control valve device 6 and atmospheric passage I58.

Upon the release of fluid under pressure from chamber 21 of the pilot valve device I, spring 3'! acts to move the valve 33 into engagement with its seat 35 thereby preventing release of fluid under pressure from chamber 26 and consequently from connected volume reservoir 3 I.

Now when the pressure of fluid in the brake pipe I has'been increased to a degree sufiicient to effect operation of the brake controlling valve device 2 to release position which is approximately 50 pounds with the AB control valve device the brake cylinder II will be connected to the atmosphere in the usual manner thereby vent- 'ing fluid under pressure therefrom. When this occurs the push rod ill will move into the cyl-'- inder and thereby cause the cylinder levers I2 and I3 to effect a release of the brake on the vehicle and when the roller I41 traverses the right hand end of the slot I48 a clockwise rocking movement about pin I45 is imparted to the lever I43, the outer end of the. lever acting through the medium of rods I40 and I42 to actuate the toggle links I36 and'I31 and the arm 60 of the pilot valve device I, all of which will -be clear from the previous description of a release of the brakes after a serviceapplication of the brakes.

As the arm 60 of the pilot valve device'I is thus actuated it rotates the high point 58 of the cam 51 out of engagement with the member 39 thus permitting the spring 39a to rock the member 39 about its pivot pin 3%. As the member 39 continues to rock the spring seat 54' is moved into engagement with the stop ring I50 and con-. tinued movement causes the valve piston 5I to be moved out of engagement with its seat 52 while the valve piston 44 is still maintained in seating engagement with its seat. With the valve piston 5| unseated and the valve piston 44 seated fluid under pressure in chamber 30 and connected reservoir 3| flows to chamber I23 of the locking mechanism I0, past unseated valve piston 5|, through passage 43, chamber 40 and pipe 4|. Fluid under pressure thus supplied to the chamber I23 of the locking mechanism eflects operation of the locking mechanism in identically the same manner as described in connection with initial charging of the equipment. That is to say, the locking mech anism I0 will function to unlock the adjusting mechanism 9 and thus permitthe weighing mechanism 8 at each end of the vehicle to position the adjusting vehicle. Now as the member 39 continues to rock about its pivot pin 3% the spring seat 48 is moved into engagement with the stop ring I5I and continued movement of the-member 39 will move the valve piston 44 out of seating engagement with the seat rib 45.

When this occurs fluid under pressure in chamber I23 of the change-over control valve device I0 will be vented to the atmosphere byway of pip 4I, chamber 40, past unseated valve piston 44, chamber 42, and connected chamber 21-, pipe 28, cavity I5'I in the slide valve 24 of the change over control valve device 6 and atmospheric passage I58. Since volume reservoir-3| is connected to chamber 40 at this time in the manner above described, it is also vented to the atmosphere. x

Upon venting of fluid under pressure from chamber II] of the locking mechanism I23 the spring I22 therein operates as already described towlock the adjusting mechanism in the proper position in accordance with the load on the vehicle. The final movement of the member 39 causes the valve piston 44 to move into sealing engage' ment with the gasket 46 thereby cutting off com munication between chambers 30 and 40 for rea= sons previously described in connection with initial charging. v It will be understood by those skilled in the art that'it is not practicable to provide the forces needed to shift the rod and its associated pins 9I and 93 while the brake is applied therefore the pilot valve device I and associated volume res-'- ervoir 3I are provided for the adjustment of the brake mechanism after the brake is released and according to the weight of the load carried.

Embodiment shown in Figs. 8, 9 and 10 form of mechanism for locking the adjusting mechanism 9 in its adjusted position which may be substituted for the locking mechanism shown in Figs. 1 and 2. The locking mechanism is indicated by the reference numeral 200 and is similar to the mechanism shown in Fig. 1, but differs therefrom in that the locking plates I06 and the actuating lever I I3 are omitted and the spring seat I I1 is connected to one end of a slidably mounted member 20 I which member, at its oppo site end is'adapted to be engagedby the stem I I5 of the piston IIB. y 1

As best shown in Fig. 10 of the accompanying drawings the member 20I is provided with a recess 204 in which there is disposed a gear wheel 205 provided with teeth arranged to engage looking teeth on the member 20I. The gear wheel 205 is mounted on a shaft 206 which is journaledin the casing of the mechanism. One end of this shaft extends (to the exterior of the casing and has mounted thereon a, pinion gear 201 arranged to engage rack-teeth provided on the end of the rod 99. h As will be understood from the description ,of the apparatus illustrated in Fig. 1, fluid'under pressure supplied to pipe 4I effects operation 0f the piston H5 in a direction toward the left hand. Movement of the piston in this direction causes the piston stem I I5 to engage the member 29! and continued movement of'the piston and stem moves the member 20l in the same direc' tion against the opposing pressure of the spring l22, thus moving the teeth on the member out of engagement with the teeth on the gear wheel 205.

When the member 20l is moved out of engage-' ment with the gear wheel 205 any change in the load on the vehicle will as hereinbefore de or inwardlyof the rod efiects; notatiomcf the pinion vthreby thegear 205.- l r Now when; the change-oven control valve. device it operates. as; described in. connection with the I first. embodimentoi} the invention a to. releasefluidiunder-pressurefrom the pipe 4:|=,.the; spring.- iZ-Zawill act. to. move the. tooth portion, ofiathe. member 291 into eneaaementwiththe:teeth: on the gear wheel-20.5. and thusdock the nodzQBin the; adiiustedpositiom i i Description of the embodiment shounr in Fig: 1'1

In llsthere isillustrated another form of the invention. showminFig, Lin which arod and lever weighing mechanism. is. substituted for the cable. and. pulley weighing mechanism disclosed; in Fig.1. In! addition to-the. rod and lever weighing; mechanism, a locking mechanism. different substituted and the toggle mechanism I35 is, omitted. For simplicity, corresponding parts and pipeslof'. the two embodiments willihe designated fromthat shownlinE-igh1 .01 Figs. 8.;.9.,,ar1d; 10. is i by the same reference. numerals without. further description andonly; those parts provided in Fig. 11, which are; notprovidedin. the previous em.- hodiments will be described briefly in. connection with; thepbasic parts. on the. equipment. l

Asishown in Fig. 11. ofthe drawings the live cylinder, lever. 1.2, is providedwith an. extension 302 arranged to carry a roller whichfi'sguided inlaguideslot 3% which correspondsto; the guide slot lb in,the.apparatusofFig. 1..

In this. embodiment of. the invention. anfadiusting mechanism 300 is provided. for shifting the. rod 90. This mechanism comprises. a. shift.-

ing member 391 in which the rod. 90 is: slidablyv mounted for. longitudinal,movement... The shifting member 31H is provided. with a. horizontally extending. arm 3i) 3, which extends through. and is slidably, guided in. the fixed casing of a. locking mechanism 30.4 and at its outer. end. is. connected to on e. end of a 1ink.30.i by means of. a pin. 30,6.

Interposed, between and. operativelyengaging the outer Wall of thecasingfor thellocking mechanism 30.4 and. the. shifting member 301. is a l i spring 308.. a

Thelocking. mechanism 304. comprisesa piston 309 having a. stem..3..l0.which.is slida'bly mounted in thecasing. This stem is, provided with a slot or opening, 3| I through which the, outer endlportionof, the. arm 303 passes; This portion. ofthe arm is. provided. with looking teeth adapted. to

engage locking, teeth provided onthe stem 31])".

. end 01 a red. 3421 an arm3l-I of a; threeiarmedibell cnanklever. 320. The bell crank "lever. 3-2-0i-as well as the brake cylinder; l 1:, thedocking mechanism 304and brake cylinder leverselz and Hare mounted onamovable part of' the vehicle, suchior instancelasthe vehicleibodyi: it i The.- bell .cranlris pivotally mountediand is PEG. vided. wither-ms 32 land 32min addition to arm 32L i i The arm 323 is connected to one end of :a. link 321; While the-arm: 322" is, connected to/ one end ofi a-rod325. The link 32'! isconnectedr atits.

oppositeend to an arm" 3218 of a; bell crankieven 329;:which is, pivotally mounted on. the vehicle body. The; other arm 3.3moithe bell crankieven 32am: connected; to one end; of; a rod 331, which rod in turn isconnected: atlits opposite. end to oneend: ofta lever rial-which is pivotallylmounted.

on the casing. .a weighing; device 333 disposed atione end; ofi the vehiclezand. fixed; to; themehicle Thewlever. 332 is. operatively: connected; to,- one Bnd Qfl a push: rod, 340,. whichi push rod is. also operatively connected. to one rarm of aibell crank 341..piuotally connected; to themasingflof the weighing: device--333;by; means of a pin 3: The other arm of the {bell crank is connected toione The. nod. 3.4% is. provided. at its. opposite end; witha foot. 15. which; isadapted tohe, movsed into engagement with; the: stop 16 mounted on, the vehicle truck. frame forthe pucpose .hereinbefore described in. connection with the embodiment showninFig. 1 oftheurawings.

Contained. withinw the, casing" of. theweighing device 333 there a, movable abutment which may; bein the form. of a, diaphragm; not shown;

which. is adaptedto, actuate. the. push rod 3.40 i in a direction away from the casing to. cause movement. on the; rod 33i-in the opposite direction and to -attthejsame time causethe bell-crank lever34i to rock; about the. pivot pin 34A,, upon Zhe supply of fluid under prcssurelthroughlpipe The rod-32 dextendsto theopposite end on the. vehicle and is operatively, connected inidenti cally the same. manner asihstdescribedinconnectionl with. red 33;. to aweighing. device-333,

. not. shownt-toueiiect movement; oitherocL 32% in Engaging the end.ofthe.stem.3.fll" and the inner wall ofthe. casing is a spring. 3 [2. which. tends;,at allltimes to urge the teeth on the stem into look-- ing. engagement with theteeth on the arm303'.

At one side of the piston. 339 is alchamber3 l3 which is in constant. open communication with the. atmosphere through a passage 314'. This chamber is also connected by Way of passage and pipe 3| 5 to. the pipe 64 which. extendsfromthe weighingdeviee atoneend of. the vehicleto the weighing device attheoppositeend of the vehicle.

At the oppositesicle of the piston there. is. a

chamber 3 |6,Which-is.in.constant opencommuadirection. towardthe. left, hand; when .fluidlunder pressure isnsupplied to. the weighi'ng; device at this endof .thevehicle= ,From the. foregoing description. in connection withmhe first embodiment. of. theinvention it. will he understood that inlinitially charging the apparatus fiuidLunder. pressure will. be. supplied frormthebrake pipe to. the pipe. 22, through the circuit traced. in connection. withtherfirst. em.-

bocl-imentj unden Dressurethussuppiiedtd pipe .22 flows, therefrom through; the changeeovercontrol. value. device Gil 1L pipe 28... under pressure thus suppliedito pipe i8 flows. therefrom to chamber .ala in the: locking mechanism. 3.04.

and from. this char 'ber, itfilowsihroug-hthe res strictcdl pgassage 3 i-Ltotthe) chamber 3 i3: the 01212951138 side'of the, pistonby; way'oil, pipes: 3:419.

and. 64 and pipe and passage? 31:5; Fluidtunden pressurethus supplied. to.- pipeztkficws; to: the

1 weighing devices.- assat.-th& ends of the: vehicle for aep uripose heneinaitendesoribedi. i

Flluid under pressure acting in; chambenati causes.thepiston-.-3t9. and thereby the stem: mtoimove in a. direction toward the. left hand as. viewed in Fig. 11, against the opposing pressure of the spring. 3.1% Moiiement: of; the: 1 steini 3d 0 in this direction causes the teeth carried: thereby carried by the vehicle.

fluid under pressure to the weighing device at the restricted rate is for the purpose of providing a cushion pressure in the cylinder of the weighi'ng devices "in case the adjusting mechanism is in load position when the mechanism is unlocked in the manner just described.

Fluid under pressure supplied to the weighing device 333 at each end of the vehicle causes the push rod 300 in each device to move in a direction away from the casing thus causing the lever 332 at each end of the vehicle torock about its pivot and at the same time causes the bell'crank lever 34! 'to rock about its pivot pin 344. The

lever 332 and the bell crank lever 3 will continue to rock about their pivot pins until they are brought to a stop by the foot engagingthe stop 16. Since the rod 325 moves'to theleft and the rod 33i moves to the right upon rocking action of the lever 332 at each end of the vehicle, theselevers both act to rotate the bell crank lever 320 in a counter-clockwise direction about a pivot pin 346. It will be seen from an inspection of the drawings that the movement of the rod 325 is transmitted directly to the bell crank lever 320 while the movement of the rod 33! is transmitted to the bellcrank lever 320 through themedium of bell crank lever 330 and link 321.

Since as hereinbefore described in connection with Fig. 1 the clearance or travel between foot 15 and the stop 16 is dependent on the load carried by the vehicle, the degree the bell crank lever 320 will be rotated in a clockwise direction as just described will also be dependent on the load carried by the vehicle. 1

The counter-clockwise rotation of the bell and 93 in an adjusted position. At the same time as the piston moves in this direction it uncovers crank .320 acts through the medium of the link I 305 to move the arm 303 and thereby the member 30I outwardly against the opposing action of the spring 308 to the degree suitable for the load As themember 30l is thus moved outwardly the rod 90 carried thereby is also moved in the same direction to position the pins 9| and 93 in the slots 92 and 94.

Now; as in the previous embodiment, when the pressure in the brake pipe I and consequently in chamber'2l of the change-over control valve device 6 has been increased to approximately thirty pounds, the change-over control valve device 6 ,willfunction to release fluid under pressure from the chamber-3 l 6 in the locking mechanism 304 to I the atmosphere. When the pressure in chamber 3H5 and acting on piston 309 has been reduced below the force of the spring 3|2 said spring will act to move the piston and stem M0 in a direction toward the right hand. Movement of the piston in this direction closes the passage 3l5 temporarily thereby permitting the small volume in chamber 3H5 to reduce rapidly to atmospheric pressure. It will be noted that the ball check valve 318 acts at this timeto prevent back flow of fluid under pressure from pipe 64 'to the chamber 3l6.

Continued movement of the piston in the same direction causes the teeth on the stem 310 to enthe passage 3l5 thus connecting passage 3l5 to chamber 3l3. When this occurs fluid under pressure in the Weighing devices 333 is vented to the atmosphere by way of pipe 64, passage and pipe'3l5, chamber 3l3 and passage 3H; 7

It should here be noted that if the load on the vehicle is equally distributed on the two trucks the clearance between the shoe 15 and'the stop a When it. is desired to effect an application of the brakes fluid under pressure will be supplied to the brake cylinder II by way of pipe I60 in the manner previously described in connection with the first embodiment of the invention. Fluid under pressure supplied to the brake cylinder H will cause the piston push rod 8| to ef fect operation of the brake cylinder levers l2 and l3to cause the pull rods 83 and 88 to apply the brakes.

i It should here be mentionedthat the supply of fluid under pressure to the weighing devices at the restricted rate is' for the purpose of providing a cushion pressure in the cylinder of the weighing devices in case the adjusting mechanism is in load position when the mechanism is unlocked which is accomplished in a marine which will now be described. When the rod 901s positioned for braking on a loaded vehicle it will be moved from the position in which it is shown in Fig. 11 to a position nearer the locking mechanism 304, in the manner above described, thus spring 308 will at this time be under considerable compression. I

If under these conditions the brake pipeprese sure is reduced to below thirty pounds, as by effecting an emergency application of the brakes,

end of the vehicle and builds up a slight pressure therein before the unlocking mechanism operates to unlock the adjusting mechanism 300. Now when the unlocking mechanism does function to unlock the arm 303 of the adjusting mechanism 300, the slight pressure in the weighing device s operates through the associated lever mechanism to gradually move the shoe 15 into engagement with the stop 16 thus preventing any damage to either the shoe or the stop. At

the same time this action of the weighing mechanism will oppose action of the spring 308'to force the arm 303, member 30! and associated rod and pins 9| and 92 in a direction toward the brake cylinder II, as will be clear from'the foregoing description, thus preventing any undue strains or stresses in the adjusting mecha nism.

Having now described my invention what- I claim-as newand desire tosecure by Bette-rs Patent, isr

I. In a variable-load brake apparatus fora ve hicle, in combination, a brake lever, means for actuating said lever, an adjustable fulcrum for said lever, said fulcrumhaving a position for pro:- viding empty vehicl'e braking and being-movabletherefromto various other positions-through aloaded vehicle zone, for providing loaded vehicle braking; means movable by fluid pressure and according to the weight of the load carried for positioning said fulcrumin said loaded vehicle zone, locking means normally locking said fulcrum in position, fluid pressure controlled means having a chamber normally connected" totheatmosphere, said meansbeingoperative upon an increase in fluid under'pressure in said chamber tofirst unlock said fulcrum and thensupply fluid under" pressure to the second mentioned means to effect the positioning of said fulcrum and 01m erative upon; a decreasein fluid under pressure in said chamber to effect operation of said looking means to lock said fulcrum in, the selected position and to then release fluid under" pressure from the firstmentioned means.

2. In a variable load brake apparatus for a vehicle, in combination, a brake-lever, means for" actuating said lever, an adjustabl fulcrum for said lever, said fulcrum having a position, for

providing emlpty vehicle braking-and beingmovable therefrom to various otherpositions through a loaded vehicle zone for providing loaded vehicle braking, means movable'by'fiuidpressure and according to the weight of, the load carried for positioning said fulcrum in said loaded vehicle zone, lockingmeans for locking said fulcrum in ofithe lever intermediate-itsends, afulcrum ele ment'f'orsaid lever'disposed' in, saidslotted openingymeans movable by fluid pressure and according to the weight of the load carried: for shifting said fulcrumelement along the lever, abrake pipe adapted'to be charged with fluidito-a certain predetermined pressure, a lockingmeans for loclcthe-locking means tolockthe fulcrum and means normally establishing communication through which fluid under-pressure is supplied from the brake pipeto effect the operation of said abutment and operative before said certain predetermined pressure is attained inthe brake pipe for releasing fluid under pressur acting on said movable abutment.

5 In a variable load apparatus for a vehicle; in combination, a brake lever, a brake cylinder operativelyconnected to said lever, an adjustable,

fulcrum for said lever, said fulcrum havinga brake controlling positionfor an empty vehicle for actuating'said brake lever.

any selected position, a brake pipe normally'de plete, of fluid under pressure adapted" to be charged with fluid underpressure; for control of thebrakes on the vehicle, means operative UlpOIl a predeterminedjincrease in brake pipe pressure to effect operation of the locking means'to unlock said. fulcrum andsupply fluid under pressure to. the second mentioned means, and means operae tive upon a predetermined greater increase in brakefpilfie pressur for effecting the, operation of thelocking means to. again lock the fulcrum against movement and to release. fluid under pressure fromth second mentioned means. 3., In, a variable load brake apparatus for a. vehicle, in combination, abrake lever operatively connected at one end to-a brake rigging element:

to be operated. a brake cylinder connected'to the other end of. said' lever and operative to actuate. the leverand thereby said element, aslott'ed' opening, in said lever extending longitudinally of the'lever intermediate its ends, afulcrum elernentfor said lever disposed in said slotted opening, means movable byfluid pressure and according, to, the weight of the load carried for shifting said fulcrum element along the lever, a brakepipe adapted to be charged with fluid to a, certain predetermined pressure, and valve means responsivetc the pressureoffl'uid in the brake pipe before said predetermined pressure is attained for supplying fluid under pressure to saidmeans. p I

, 4.1m a variable load brake apparatus, for. a vehicle, in combination, a brake leveroperatively connected. at-one end to a brake rigging element to be operated, a brake cylinder connected to the other end, of said lever and operative toactu ate, the lever and. thereby said'felement, aslotted opening in said lever extendinglongitudinally and beingmovable therefrom to various other brake controlling positions through a loaded-ve' hicl zone, means movable by fluid under pres sure and? according to theweight ofthe load carried for selectively moving said fulcrum to the appropriate one of said other control positions,

and a lever mechanism operatively associated with said brake cylinder for also moving said fulcrum', said lever mechanism being operative a an incident to the operation of said brake cylinder 6. In a variable load apparatus for a vehicle, in combination, a [brake lever, a brake cylinder operatively connected to: said l'ever, an adjustable fulcrum for said lever, said fulcrum having: a brake controlling position for an empty, vehicle and being movable therefrom to-various other brake controlling positionsthrough a loaded vehicl'e zone, means movable byfluid under pressure and according to theweight of the load car-- ried' for selectivelymoving said fulcrum totheappropriate one of said other control positions,

a toggle mechanism operatively connected to said fulcrum formoving said fulcrum, and a lever mechanism operatively connectingsaid brake cylinder and toggle mechanism, said lever'mechanis'm being operative upon operation of said brake'cylinder to actuate saidbrake cylinder lever to effect operation of said toggle mechanism. 7. In a variable load apparatus for a vehicle,-

in combination, a brake cylinder lever, a brakecylinder operatively connected to said lever, an adjustable fulcrum for said lever comprising a fulcrum pin and a pin carrying element, said pin and carrying element having a brake controlling position foran empty vehicle and being movable-therefrom tovarious other brake controlling positions through a loaded vehicle zone, a member operatively connected to'said carrying element for moving said element and thereby saidpin to one of said other brake controlling positions, fluid pressure responsive meansoperative uponthe supply of fluid under pressure thereto formoving said member, and locking means comprising a plurality of slidable plates adapteduto engage said member to lock said member and thereby-said carrying-means and said pin inany selected controlposition. 8:1n-a variablerload apparatus for ayehicle;

in combination, a brake cylinder lever, a brake cylinder operatively connected to said lever, an adjustable fulcrum for said lever comprisinga fulcrum pin and a pin carrying element, said pin and carrying element having a brake controlling position for anempty vehicle and being movable therefrom to various other brake controlling positions through a loaded vehicle zone; a member operatively connected to-said carrying element for moving said element andthereby said pin to one of said other brake controlling positions, fluid pressure responsive means operative upon the supply of fluid under pressure thereto for moving said member, locking means normally locking said member against movement, said locking means comprising a ,plurality of movable plates and spring means for moving said plates into locking engagement with said memher, and a movable abutment responsive to an increase in fluid under pressure for efiecting movement of said plates out of engagement with said member to unlock *said member and at the same time to open a communication through which fluid under pressure may be supplied to said fluid pressure responsive means.

.9. In a variable load apparatus for a vehicle, in

combination, a brake cylinder lever, a brake cylinder operatively connected to said lever, an adjustable fulcrum for said lever comprising a fulcrum pin and a pin carrying element, said pin and carrying element having a brake controlling position for an empty vehicle and being movable therefrom to various other brake controlling positions through a loaded vehicle zone, a member operativelyconnected to said carrying element for moving said element and thereby said pin to necting said levers, said rod being movable longitudinally of the levers to vary the braking ratio of the levers, fluid pressure responsive means operative in accordance with the weight of the load on the vehicle for actuating said-rod to provide the appropriate lever ratio for the weight of the load carried, and valve means operative automatically as an incident to coupling the vehicle in a train for supplying fluid under pressure to said means.

12. In a variable load brake apparatus for a vehicle, in combination, a brake cylinder, a pair of brake cylinder levers, a rod operatively conone of said other brake controlling positions, fluid pressure responsive means operative upon the supply of fluid under pressure thereto for moving said member, and locking means normally looking said member against movement, said locking means comprising a toothed Wheel adapted to be driven by said member a slidable memberadapted' toengage said wheel and spring means for moving said slidable member into locking engage-- ment with said wheel to lock said member and thereby said carrying means and said pin in anyselected brake controlling position.

10. In a variable load apparatus for a vehicle in combination, a brake cylinder lever, a brake cylinder operatively connected to said lever, an adjustable fulcrum for said lever comprising a fulcrum pin and a pin carrying element, said pin and carrying element having a brake controlling position for an empty vehicle and being movable therefrom to various other brake controlling positions through a loaded vehicle zone, a member operatively connected to said carrying element for moving said element and thereby said pin to one of said other brake controlling positions, said member having adjacent one end thereof a toothed portion, fluid pressure responsive means operative upon the supply of fluid under pressure thereto for moving said member, a toothed wheel,

necting said levers, said rod being movable longitudinally of the levers to vary the braking ratio of the levers, and fluid pressure responsive means including a fluid pressure operated motor disposed at each end of the vehicle for actuating said rod longitudinally of the levers to a position in accordance with the load carried by the vehicle. I 13. In a variable load brake apparatus for a vehicle, in combination, a brake cylinder, a pair of brake cylinder levers, a rod operatively connecting saidlevers, said rod being movable longitudinally of the levers to vary the braking ratio of the levers, means including a fluid pressure operated motor disposed at each end of the vehicle for actuating said rod longitudinally of the levers to a position in accordance with the load carried by the vehicle, and locking means for looking said rod in any adjusted position.

14. In a variable load brake apparatus for a vehicle, in combination, a brake cylinder, a pair 'cle for actuatingsaid rod longitudinally of the levers to a position in accordance with the load carried by the vehicle, locking means normally locking said rod against movement, and fluid pressure valve means operative when the pressure of fluid supplied thereto is below a predetermined degree to efiect operation of the locking means to unlock said rod and at the same time supply fluid tothe fluid pressure operated motor at each end of the vehicle and operative when the pressure of fluid supplied thereto is above a predetermined degree to effect operation of said locking means toagain lock said rod and to release fluid under pressure'from said fluid pressure operated'motor at each end of the vehicle.

15. In a variable load brake apparatus for a vehicle, in combination, a brake cylinder, a pair of brake cylinder levers, a rod operatively connecting said levers, said rod being movable longitudinally of the levers to vary the leverage ratio, a lever mechanism operatively connecting said rod and said brake cylinder, operative upon operation of said brake cylinder to effect an application of the brakes for actuating said rod to a position relative to the length of said levers to take up slack, fluid pressure responsive means operative upon the supply of fluid under pressure thereto for also actuating said rod' to a position relative to the length of said levers in accordance with' the load carried by the vehicle, and valve means automatically operative upon operation of said brake cylinder to efiect a release of the brakes for supplying fluid under pressure to said fluid pressure responsive means.

16. In a variable load brake apparatus for a vehicle i'n combination, a brake cylinder, a pairof effect the unlocking operation of the fluid pressure responsive means,- said valve means being operative upon a predeterminedincrease in brake pipe pressure for closing said communication, "a reservoir normally deplete of fluid under pressure, a valve device operative upon the operation'of said brake rigging to effect an application of the brakes to cut off communication through which fluid under pressure may flow from the brake pipe to said fluid pressure responsive means'when said valve means is in its normal position and to establish communication through which fluid underpressure may flow from said brake pipe to saidreservoir and operative upon the operation of saidbrake rigging in effecting a subsequent release of the brakes after operation of said valve means by said predetermined increase in'brake pipe pressure to supply fluid under pressure from said reservoir to said pressure responsive means.

23. In a variable load fluid pressure brake-sys term for a vehicle the combination with abrake pipe, a brake cylinder and a brake rigging operative to eflect an application and the release of the brakes of means movable accordingto variations in the weight of the lading carried by the vehicle for varying the braking power of said brake rigging, fluid pressure responsive means operative upon a reduction in the pressure of fluid acting thereon to lock said means in any position to which it has been moved and operative upon an increase in the pressure of fluid acting thereon to unlock said means, valve means normally establishing communication through which fluid under pressure may flow from said brake pipe to said fluid pressure responsive means to effect the unlocking operationof the fluid pressure responsivemeans, said valvemeans being operative upon a predetermined increase in the brake pipe pressure for closing said communication, a reservoir normally deplete of fluid under pressure a valve device having an application position and a release position said valve device being movable from said release position to said application position upon the operation of said brake rigging to effect an application of the brakes to render said valve means ineffective to control the flow of fluid under pressure to and from said pressure responsive means and to render said valve means effective to establish a communication through which fluid under pressure may flow from said brake pipe to said reservoir for charging same and movable from said application position to said release position upon the operation of saidbrake rigging to effect a subsequent release of the brakes to supply fluid under pressure from upon a reduction in the pressure of fluid acting thereon to effect operation of said spring means to lock-said means and operative upon an'in' crease in the pressure of fluid acting thereon to enect operation of said'spring means to unlock said means, a valve having one position for establishing communication through which fluid under pressure may flow from said brake pipe to said fluid pressure responsive means and having another position for cutting off communication from the brake pipe to said fiuid pressure responsive means and establishing communication through which fluid in'said fluid pressure responsive means is vented to the atmosphere, means responsive to the pressure or fluid in said brake pipe for controlling said valve and'normally operative to maintain said valve in-said one position and operative upona predetermined increase in brake pipe for moving said valve to said other position, a valve device interposed betweeirsaid valve and said fluid pressure responsive means operative upon the operation of said brake rigging to effect an-application or the brakes to render said valve'ineflectivato control theflow'of fluid under pressure to and from said pressure responsive means and operative upon the operation of said brake rigging inef- 'fecting' a subsequent release of the'brakes to ervi'or, a third passage through which fluid under pressure is adapted. to'be supplied .from the ins'upply fluid under pressure from a source other than said brake pipe to 'said fluid pressureresponsive means. 1

25. In-a variable load brake for a vehicle com} prising'a levermechanism operative to apply and release the brakes; a brakecylinderfor controlling the operation of said lever mechanism, said brake cylinder being operative upon a'supply'of fluidunder pressure thereto for effecting operationof the lever mechanism toapply the brakes andupon a release of fluid under pressure there;

from to effect operation of the-lever mechanism to release the brakes; adjusting apparatus opera tive according to variations in the weight'of the 'load' carried by the vehicle to condition said mechanism for empty braking or load braking;

means for locking said adjusting apparatus against operation when the brakes are applied,

said means including a locking mechanismsresponsive to'an increase in fluid pressure thereon for unlocking the adjusting apparatus and op erative upon a decrease in fluid pressure thereon for locking said adjusting apparatus, a reservoir normally deplete of fluid underpressure, a valve mechanism provided with a first passage through Which fluid under pressure is adapted to be supplied to theinterior thereof, a second passage through which'fluid under pressure is adapted to be supplied from the interior of the valve mechanism to and released from said resterior of the valve mechanism to and release 'from the locking mechanism and beingmoperative by the brake cylinder as the brake cylinder moves to application position to establish communication between said first and said second passages and operative by the brake cylinder as the brake cylinder moves to release position to first establish communication between said second and third passages and then between said first, second and third passages; a brake pipe normally charged with fluid under pressure to a predetermined degree; and a valve deviceresponsive' to the pressure of fluid in the brake pipe and operative when the brake pipe pressure is a certain degree below said predetermineddegree for establishing communicationthrough "which fluid may :flow from said brake pipe to said first passage and operative upon an increase above said certain pressure for connect 'ing said first passage to the atmosphere.

CLYDEJ C. FARMER. 

